Deception detection is of significant importance to both Intelligence and Law Enforcement Agencies. The standard approach for deception detection is the polygraph, an approach that has existed for 90 years. The polygraph uses a combination of heart rate, blood pressure, respiratory rate, and skin conductance to provide feedback to a human “expert.” By monitoring this biometric data while asking a series of baseline yes/no questions, followed by the questions of interest (typically also framed as yes/no questions), the expert is able to make a prediction as to the subject's honesty.
However, there is significant debate over the quantitative accuracy of polygraph tests, the results of which are not admissible in court. As a result, polygraphs are often used largely as deception deterrents (as opposed to deception detectors), identifying deceivers as those who decline to be tested.
Furthermore, the requirement of placing biometric feedback sensors on an interview subject creates an artificial environment that can affect the behavior and physical state of the polygraph subject, and can cause the subject to exhibit a heightened reluctance to being interviewed and tested, even if there is no intent to deceive.
What is needed, therefore, are improved techniques for detecting deception on the part of an interview subject that do not require biometric monitoring of the subject.